Vat-dye and process of making same.



- UNITED STATES PATENT OFFICE.

KARL SCHIRMACHER, F HOOHST-ON-THE-MAIN, GERMANY, ASSIGNOR TO FARBWERKE, vORM. MEISTER, LUCIUS &. BRUNING, OF HOGHST-ON THE-MAIN, GERMANY, A CORPORATION OF GERMANY.

VAT-DYE ANDPROCESS OF MAKING SAME.

Specification of Letters Patent.

- Patented. June 12,1906.

Application filed December 21, 1905. Serial No. 292,859.

To' all whom it may concern."

Be it known that I, KARL SOHIRMAOHER, Ph. D., chemist, a citizen of the Empireof Germany, residing at Hochston-the-Main, Germany, have invented certain new and useful Im rovements in the Manufacture of New Vatyestufis, of which the following is i v vat and dyeing therefrom green shades.

The glycin of dianthranilic acid hitherto unknown may be prepared as follows: 31.6 kilograms of sodium dianthranilate are dissolved in water and a solution of 25.0 kilograms of sodium chloroacetate is added.

: The solution is heated in a reflux apparatus until the quantity of the separating yellowbrownish product no longer increases. It is filtered and washed with water. Warm water is poured over the residue, sodium carbonate being added until feeble alkaline reaction, and the solution is then evaporated to dryness to obtain the neutral glycin salt.

The manufacture of the dyestuif occurs, for instance, as follows: Twenty kilograms of the glycin sodium salt are introduced into a mixture, heated to about 250 centigrade, of about twenty kilograms of caustic soda lye and twenty kilograms of caustic potash and heated to 270 to 280 centigrade for a short time. When cold, the mass is dissolved in water, and the new vat-dyestuif is then separated by oxidation, preferably by blowing in air, as green flakes. Itis insoluble in water and the usual solvents. In concentrated sulfuric acid it dissolves to a green solution. It dyes, reduced to a vat, 'very fast green shades.

Having now described my invention, what I claim is 1. The process for the manufacture of a vat-dyestufi, which consists in heating the glycin of dianthranilic acid with alkalies and oxidizing the indoxyl melt thus formed in the usual manner.

2. The process for the manufacture of a vat-dyestuff, which consists in heating the glycin of dianthranilic acid with alkalies and in presence of a chemical capable of binding water and oxidizing the indoxyl melt thus formed in the usual manner. v

3. As new product the vat-dyestuif obtained by heating the glycin of the dianthranilic acid with alkahes, being a dark green-black owder insoluble in water and the usual so vents, soluble in concentrated sulfuric acid to a green coloration and reducible to a vat from which it dyes in fast green shades.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

KARL S'CHIRMAOHER. 

